"Santorum is the third 2012 presidential candidate to release tax returns. Former House Speaker Newt Gingrich released his 2010 returns, and former Massachusetts Gov. Mitt Romney made public his 2010 and 2011 returns.

"Santorum released the most information of any candidate, and the forms show he paid a higher tax rate than Romney, who paid about 14 percent on mostly unearned income from investments, and a slightly lower rate than Gingrich, who paid about 32 percent in taxes.

"Each year, the Santorums gave between $13,000 and $30,000 to charity, with a maximum of $29,882 in 2009. In 2010, he gave $16,289 in charitable donations."

USA Today reports that Santorum used the tax returns as an opportunity to distinguish himself from Romney and stress his blue-collar roots. They report:

"In an interview on CNN Wednesday night, Santorum noted that two of his seven children are in college, his youngest daughter has a genetic disorder requiring care, and he has a house that lost value in the economic downturn.

"'I took a lot of that money and actually paid down a rather significant mortgage to the point where ... my mortgage was still below the value of my house,' Santorum said. '...We've had some expenses and we've been very blessed to have the opportunity to be able to handle those and still be ... in the black.'"

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